PROJECT SUMMARY/ABSTRACT ? Resource Core The Special Mouse Strains Resource (SMSR) at The Jackson Laboratory (JAX) is committed to ensuring ongoing access to specialized mouse strains for analysis of complex traits. The current SMSR collection includes Recombinant Inbred (RI) lines and Chromosome Substitution (CS) strains. SMSR will continue to support the provision of these strains by archiving, breeding, and distributing from high health status facilities with state-of-the-art quality control and husbandry practices. The SMSR will also maintain complete, accurate and accessible information resources, and customer service. To evolve its collection, the SMSR will work closely with the complex trait community and strive for self-sufficiency. Finally, the SMSR will provide outreach and collaborative opportunities for the development of new resources, like the Collaborative Cross and Diversity Outcross strains, and for access to large-scale breeding and phenotyping facilities.